You can start by getting your child a bike, since he will be able to pedal well by now. Make sure it is of good quality, and is sturdy. He will still need help, so make sure the cycle has supporting side wheels which are dependable.
You can also give your child some simple toys which need assembling. This can include a building set, or even some kitchen set and garage set.
Try and give your child a board and some chalk to scribble with. This will not only give the child a very good chance at having fun, but will also help him improve his ability to hold and write better. He will also have a lot of fun erasing with the duster.
Your child should be able to string things together well. Give him some large beads and shoelace, and ask him to string the beads onto the lace. He should be able to do this, and can also keep himself busy for a while.
You can give your child some simple jig saw puzzles which have eight or ten pieces. While you might need to guide him the first time, he can get about by himself quite easily on his own after this. Make sure the pictures are familiar to him.
Your child should know the name of most colours by now. Get him some simple games which involve colours and colouring. You can also get him colouring books, but do not expect him to stay within the lines or use the right colours unless he is guided.
You can also buy your child some games which talk about animals, birds, fruits, flowers and animal homes. There are plenty of these which are available as games, and your child will learn as he is having fun. Make sure that there is some element of learning in the games that you give your child since he will be able to learn a lot at this stage, and constantly has the need to be stimulated.
Play games with your child which involve taking turns and sharing. This should encourage and drive home the point of playing with others. He can pick this up very easily.
Try and do some finger painting and some straw painting as well. This will help him learn and play well.